Bao Xin 1800mAh Standard Li-ion Backup Battery For HTC A9191, Desire HD, Inspire 4G/Ace/G10, HTC 7 Surround T7878 Profession Battery with Brand High capacity business battery for HTC A9191.All applicable models below in description.No NFC Charging voltage:4.2V;Output voltage: 3.7V; Capacity: 1800mAh; No Memory Effect,Environmentally Friendly.Smart overcharge ,short circuit protection Made with Grade A Li-ion cells and highest quality raw materials. Certified by CE / RoHS Can be charged in phone or charger,available for more than 500 times recharge cycles